The process of reproductive aging centers on the generally accepted principle that human oocytes peak in number during fetal life, undergo atresia thereafter, and do not regenerate. Although female fertility declines with age, it is difficult to predict the pace of reproductive decline in an individual woman. Nonetheless,clinicians often are asked for advice on fertility potential and recommendations for fertility treatments. This document reviews the evidence relating to the clinical utility and predictive value of ovarian reserve testing. An understanding of the limitations of screening tests in general, and ovarian reserve tests in particular, is required to avoid confusion and misinterpretation, or misuse of results.